Hoisting device



Nov. 5, 1963 P. K. EELLS EI'AL 3,109,628

HOISTING DEVICE Filed May 3, 1961 6 Sheets-Sheet 1 EN TOR5 A Tram 12yNov. 5, 1963 P. K. EELLS ETAI. 3,109,628

HOISTING DEVICE Filed May 3. 1961 6 Sheets-Sheet 2 Pig 2.

mmvrons PAUL K. EELLS wmum FWRIGHB-JR.

ZJQ/W Nov. 5,- 1963 P. K. EELLS ETAL 3,109,623

HOISTING DEVICE Filed May 3, 1961 6 Sheets-Sheet 3 INVENTORS PAU L K- EE LLS Nov. 5, 1963 P. K. EELLS EIAL 3,109,628

HOISTINGDEVICE Filed May 3, 1961 6 Sheets-Sheet 4 PS-4m j 23; y

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INZENTORS PAUL K. EhLLS it v yuuAm E WRIGHTMR.

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A TTORNIF/ Nov. 5, 1963 P. K. EELLS ElAL 3,109,628

HOISTING DEVICE Filed May 3, 1961 6 Sheets-Sheet 5 Fig 5 ZZZ Z4 INV ENT0115 PAUL K. EE LLS A Tram/a & y yl LLIAM F? WRlGHT,dR.

1963 P. K. EELLS ETAL 3,10 ,628

HOISTING DEVICE Filed May 3, 1961 6 Sheets-Sheet 6 INVENTORE PAUL K.EELLS WILLIAM F. wRlsHTflJR.

United States Patent 3,109,628 IIGISTING DEVIQE Paul If. Eeiis, Lisbon,and Wiiiiam E. Wright, .Iru, Saiem, Qhio, assignors to 'Ihe Wrighthuffing Wheel Company, Lisbon, Ghio Fiied May 3, 1961, 581'. No. 116,22114 tiiaims. (Cl. 254-167) The present invention relates to a manuallyoperated force applying device, more panticularly to a manually operatedhoisting device and the like, and the principal object of the inventionis to provide new and improved devices of such character.

As will subsequently appear, the present invention 0perates on thewell-known ratchet principle which has long been used for devices of thepresent type. Prior art devices, however, can be divided into twogeneral types; i.e., those which function satisfactorily but which arecomplicated and expensive to manufacture, and those which, while low inmanufacturing cost, are extremely limited in their force applying, orweight lifting, capacity. A further difficulty of many prior ant designsis that many employ complex springs or other delicate parts whichfrequently break. In contrast, the present invention provides a simplelight-weight structure which, in its present commercial form, weighs buttwelve pounds yet is capable of lifting two thousand pounds with anapplied force of but eighty pounds. The structure is relatively low incost of manufacture and employs but three springs, each of simple,long-life design and app-lication. Thus the device can be sold at arelatively low price and is practically maintenance-free. These andother advantages will readily become apparent from a study of thefollowing description and from the drawings appended hereto.

In the drawings accompanying this specification and forming a part ofthis application, there is shown, for purpose of illustration, anembodiment which the invention may assume, and in these drawings:

FIGURE 1 is a sectional view taken through a preferred form of theinvention showing the position of parts in one stage of operation andgenerally corresponding to the line 1-1 of FIGURE 2,

FIGURE 2 is a sectional view generally corresponding to the line 2-2 ofFIGURE 1,

FIGURE 3 is a fragmentary, exploded perspective view of certain details,

FIGURE 4 is a view similar to FIGURE 1 but illustrating another stage ofoperation,

FIGURES 5 and 6 are views similar to FIGURE 4 but illustratingsuccessive stages of operation,

FIGURE 7 is an enlarged, fragmentary view of a portion of a detail seenin FIGURE 2,

FIGURE 8 is a reduced size sectional view of a modified detail, and

FIGURE 9 is an enlarged, fragmentary view of a portion of the detailseen in FIGURE 8.

With reference to FIGURES 1 and 2, the device, in brief, comprises aframe It} which rotatably supports a drum 11 having axially spaced,radially outwardly extending flange portions one of which has a toothedperiphery forming a ratchet wheel 12. A shaft 13 extends axially throughthe drum, the latter being pinned or otherwise secured thereto forunitary rotation therewith. A flexible cable 14 has one end anchored tothe drum, the opposite end of the cable carrying a suitable hook (notshown) for attachment to the body to be lifted.

Pivotally carried by the frame is a holding pawl 15 which isspring-biased to engagement with the ratchet wheel. This pawl, as seenin FIGURE 1, normally prevents rotation of the ratchet wheel in aclockwise direction. Pivotally carried by axial extensions of shaft 13is an arm 16 which in turn pivotally supports an actuating pawl 17. Thispawl is selectively spring-biased either toward engagement with theratchet wheel, as seen in FIGURE 1, when the latter is to be rotated ina counter-clockwise direction or away from engagement with the ratchetwheel, as seen in FIGURE 4, when the latter is to be rotated in aclockwise direction. As will later be disclosed, oscillation of handle:16 about shaft 13 will cause rotation of the ratchet wheel andconsequently rotation of the drum in a direction to wind or unwind thecable therefrom to thus respectively raise or lower the load attached tothe free end of the cable.

Turning now to a more detailed description of the various parts andreferring first to FIGURE 2, frame 10 is formed of two, opposite handportions 19.1 and 10.2 each having respective central portions 10.3 and18.4 and respective off-set leg portions 1&5 and 1416. Frame portions10.1 and 141.2 are removably secured together by means of bolts 18 andeach central portion is recessed to receive a headed pin 1h which isrotatably clamped therebetween. Although not shown, a hook or otherdevice may be secured to the upper end of pin 19 for connecting thehoist device to a suitable support. Each frame portion 10.11, 10.2 isribbed at 1%.? for added strength and the offset portions 16.5, 18.6 arespaced from each other, as shown, and each carries a suitable bearing 26for the previously mentioned shaft 13. While sleeve bearings have beenshown for simplicity, ball or other anti-friction bearings will be usedin the production device.

Still referring to FIGURE 2, drum 11 is disposed between the frameoffset portions 10.5, 10.6 with the ratchet wheel 12 adjacent thelatter. The ratchet wheel portion of the drum provides an axiallyextending shoulder 21 on which is rotatable an actuating disk 22 (seealso FIGURE 1) later to be described in detail. The previously mentionedholding pawl 15 is trunnioned between the frame offset portions 135,10.6 in spaced relation to the shaft 13, each frame portion having anapertured ear 1th; protruding therefrom for rotatably receivingrespective reduced end portions 15.1, 15.2 of this pawl. An off-set lug15.3 on pawl 15 provides an anchor for one end of a torsion spring 23which is wound about pawl end portion 151. The other end of spring 23 isanchored to the adjoining frame portion 16.5 whereby the springyieldably biases the tooth portion 15.4 of the pawl to engagement withthe ratchet wheel. For a purpose to appear, pawl 15 has an upstandinglug 15.5 which provides for ready manual actuation thereof and the pawlhas a flat surface 15.6 which is best seen in FIGURE 1.

Turning now to the previously mentioned arm 16 and still referring toFIGURES l and 2, this arm is similar to the frame It in that itcomprises a pair of opposite hand portions 16.1, 16.2 each having arespective central portion 15.3, 16.4 and respective off-set portions16.5, 16.6. Central arm portions 16.3, 16.4 are adapted to be securedtogether by means of bolts 24, such portions being recessed to receiveone end of an elongated tube 25 which is clamped therebetween. Althoughnot shown, the free end of tube 25 is adapted to be gripped by theoperator to effect reciprocation of the arm 16 about the axis of shaft13. Off-set arm portions 16.5, 16.6 are spaced apart to spanthe off-setframe portions 1&5, 1116 and each is apertured to rotatably passrespective ends of shaft 13. Suitably secured to the latter for unitaryrotation therewith is a knob 26 whose function will later appear.

Extending between the arm portions 16.5, 16.6 is a shaft 27 (see alsoFIGURE 3) on which the actuating pawl 17 is pivoted. In addition to atooth portion 17.1 which aligned with and adapted to engage the ratchetwheel, pawl 17 has a radially outwardly extending lug 17.2 which isspaced both radially of the tooth 17.1 and axially therefrom foralignment with a portion ofthe previously mentioned disk 22 for apurpose to be seen. De-

pending from the actuating pawl 17 (in the position of parts as viewedin FIGURES 1 and 3) is a ring-like portion 17.3 whose interior, annularsurface 17.4 provides opposed, facing-abutments for a purpose to appear.

ing radially outwardly of the stub shaft 28 is an actuating finger 28.2by means of which the shaft 28 may be reciprocated with respect to thearm portion 16.6 through an arc of approximately one hundred eightydegrees for a purpose to appear.

Slidable in a transverse bore of the stub shaft 28 is a cup-like plunger29 whose closed end bears against the internal, annular pawl surface17.4. A helical spring 3% yieldably biases the plunger to engagementwith the pawl surface 17.4 to yieldably bias the pawl to the positionseen in FIGURE 1 wherein its tooth portion 17.1 is engaged with theratchet wheel.

With the construction thus far described and with the parts positionedas seen in FIGURE 1, if arm 16 is rotated in a counter-clockwisedirection, actuating pawl will be swung in an arcuate path therewith.Since this pawl is engaged with a tooth of the ratchet wheel, the latterand thus the drum will be rotated in a counter-clockwise direction towind the cable on the drum. Upon rotation aforesaid of the ratchetwheel, the holding pawl 15 will be sprung outwardly to allow a ratchettooth to pass thereunder and will immediately spring back to preventreverse rotation of the ratchet wheel. As soon as the ratchet wheel hasbeen rotated sufliciently to allow a tooth thereof to pass under theholding pawl 15 as above described, handle 16 may then be rotated in aclockwise direction to the position illustrated in FIGURE 1. It will beunderstood that during such clockwise rotation of the handle, pawl 17will spring over a ratchet wheel tooth and will be immediately returnedby spring 30 to engagement with the next adjoining ratchet wheel tooth.The above procedure will be repeated as many times as necessary untilthe load at the end of cable 14 has been lifted step by step (or moreaccurately, tooth by tooth) the required amount.

From the foregoing it will be understood that the previously mentioneddisk 22 serves no function during load elevation, instead, such diskfunctions only when the load is to be lowered. Accordingly, the plateand its associated parts will next be described in detail prior to adisclosure of the load-lowering operation.

With reference to FIGURES 2 and 4, disk 22 provides upper and lowerbosses 22.1 and 22.2 in opposed relation. Slidably carried by the upperboss 22.1 is a headed pin 31 biased to the extended position seen inFIGURE 4 by means of a helical spring 32 disposed within the boss cavityin which the pin head is slidable. Pin 31 forms an abutment for apurpose to appear. The spring 32 is retained in the cavity by means of akeeper pin 33. Formed on the boss 22.1 is a projection 22.3 whichengages with an abutment 10.9 formed on the frame portion 10. 6 to 7limit disk rotation. As seen in FIGURE 4, the free end of pin 31 isadapted to engage the holding pawl flat 15.6. beneath the pivotal axisof this pawl, for a purpose to be seen.

The lower disk boss 22.2 is provided with a threaded aperture forreceiving a screw 34 whose end opposite its head provides an abutmentdisposed in the arcuate path of movement of the actuating pawl lug 17.2.A lock nut 85 retains the screw 34 in the desired position of adjustmentrelative to the boss 22.2.

When the load supported by cable 14 is to be lowered, stub shaft 28 willbe rotated by means of finger 28.2 from the position seen in FIGURE 1 tothe position seen in FIGURE 4. Plunger 29 and spring 36 will thus biasthe actuating pawl 17 to the full-line position seen in FIGURE 4 whereinits tooth 17.1 clears the ratchet wheel. If the arm 16 is now rotated ina counter-clockwise direction from the full-line position seen in FIGURE4 to the phantom-line position seen therein, actuating pawl lug 17.2will engage the end of screw 34 to thus pivot the actuating pawl aboutits shaft 27, against the urging of the spring 31), to engagement withthe ratchet wheel. Note, however, that the actuating pawl has not yetengaged with a ratchet wheel tooth and thus the entire load remainssupported by the holding pawl 15.

Further movement of the arm 16 in a counter-clockwise direction from thephantom line position seen in FIGURE 4 to the position seen in FIGURE 5will cause the pawl tooth 17.1 to engage the adjoining ratchet wheeltooth whereby the actuating pawl will be in position to pick up the loadsupported by the cable. It will be noted that the movement aforesaid hascaused counter-clockwise rotation of the disk 22 since the actuatingpawl lug 17.2 is engaged with the disk screw 34, such disk movementbeing permitted since the path 31 has moved inwardly of the boss 22.1causing deflection of spring 32. The pin 31 and spring 32 thus functionas a resilient, lostmotion connection between the two pawls. Pawl 15still remains in the position illustrated, despite the pressure exertedby the spring 32 tending to force the pawl away from ratchet Wheelengagement, since this pawl continues to support the load and thuscannot be shifted about its ivot.

P Further movement of arm 16 in -a counter-clockwise direction from theposition seen in FIGURE 5 to the position seen in FIGURE 6 will causethe actuating pawl to pick up the load and rotate the ratchet wheelslightly in a counter-clockwise direction. As soon as the ratchet wheelhas rotated sufficiently to unlock the holding pawl tooth 15.4therefrom, the force exerted by plunger 31 will urge the holding pawl tothe position illustrated in FIGURE 6 wherein it is clear of the ratchetwheel. At this time, the entire load is supported by the actuating pawl17.

'From the position seen in FIGURE 6, handle 16 may now be rotated in aclockwise direction to permit clockwise ratchet wheel rotation andconsequent lowering of the load. During initial clockwise arm rotationand consequent similar rotation of the disk 22, pin 31, under the urgingof spring 32, will continue to maintain the holding pawl 15 away fromratchet wheel engagement until the ratchet wheel has moved sufficientlyin a clockwise direction that the wheel tooth previously engaged by theholding pawl has passed therebeneath. At such time, there will have beensufiicient clockwise rotation of disk 22 that pin 31 will have reachedthe end of its outward travel and thus will be unable to exert furtherforce to maintain the holding pawl away from ratchet wheel engagement.Accordingly, the holding pawl will once again be biased toward theratchet wheel by means of the torsion spring 23. Further clockwisemovement of the arm 16 will continue until the holding pawl is seatedagainst the next ratchet wheel tooth and supports the entire load. Atsuch time, that is with the holding pawl supporting the load, slightfurther clockwise movement of the arm will unlock the actuating pawlfrom the ratchet wheel tooth so that the plunger 29 and the spring 30will bias the actuating pawl away from ratchet wheel engagement to theposition seen in FIG- URE 4. The above precedure will be repeated asmany time as necessary until the load has been lowered toothby-tooth therequired amount.

When the cable 14 is to be rapidly wound upon the drum, as when no loadis attached thereto or when slack is to be taken out of the cable, it isonly necessary to rotate the drum and the ratchet wheel in acounter-clockwise direction by means of the knob 26. Similarly, the knob26 may be employed to rotate the drum in a clockwise direction to unwindcable therefrom when no load is attached thereto. Such operation,however, requires that the stub shaft 28 be positioned as seen in FIGURE4 so as to bias the actuating pawl away from the ratchet wheel and alsorequires that the holding pawl be disengaged from the ratchet wheelagainst the urging of the torsion spring 23 by the application ofpressure to the holding pawl lug 15.5.

While the foregoing construction functions very well, it has been'foundthat certain problems arise when a conventionally constructed windingdrum, such as seen in FIGURE 2, is employed. Simply defined, and withreference to FIGURE 7 wherein the drum 11 is fragmentarily seen inenlarged section, the problem is as follows: During elevation of a loadand when the cable 14 has been wound to the end of the drum, the nextfew turns of the cable will pile up on one another, as illustrated,instead of smoothly reversing and winding the next cable layer upon thepreceeding one. Eventually, such turns will fall into place as indicatedby the arrows and phanton lines; however, when they do, the the loadwill drop a perceptible amount.

This dropping of the load causes heavy stresses on the cable and thehoist parts and since it is unexpected, can also be quite dangerousduring certain operations. This tendency of the cable to pile up at thedrum ends is aggravated by the fact that since the hoist is suspended asingle point by its supporting hook (not shown), the axis of the drumwill tilt when the cable extends from a drum end. This is seen in FIGURE7 wherein A illustrates a plane normal to the drum axis when the cableis centered beneath the hook and B illustrates such plane when the cableis at (in the position of parts shown) the left end of the dru,

As viewed in FIGURE 8 wherein like parts are identified by the samereference characters as before but with the sufiix (1 added, a highlyeffective solution to the above-mentioned problem lies in forming adished surface 3d, 37 in the facing surfaces of respective flanges atrespective ends of the drum 11a. Furthermore, the annular drum surfaceis tapered at 38 from approximately the center line A of the supportinghook, such tapered drum surface being larger in diameter at its endadjacent the flange than at the center line of the hook.

Operation of the improved drum 11a is as follows, reference being madeto the enlarged fragmentary section FIGURE 9: As the cable 14a is woundupon the drum and reaches the left (in the position of parts shown) endthereof, the first turn 14.1 of the next cable layer will be crowdedagainst the adjoining flange surface as shown. The next turn 14.2 of thecable will, however, be Wound alongside turn 14.1 instead of on top ofthe latter, as frequently happened before, because of the followingreasons. Firstly, the angularity of the dished surface 36 will crowd theturn 14.2 to the right so that it cannot obtain sufficient support toremain on the turn 14.1. Secondly, as a result of the tapered drumsurface 38, the cable turn 14.2 will not be required to climb up hill toreach the position seen in FIGURE 9 even though the drum is tilted sothat a plane normal to its axis is shifted to the position seen at Bfrom its normal position seen at A.

It will be understood that successive cable turns will lie along thepreceding turns until the cable reaches the right end of the drumwhereupon the cable will begin to wind a third layer in the same manneras the second layer was commenced. It is also to be understood thatsince the centerline A of the hook (see also FIGURE 8) is not centeredbetween the drum flanges but is off-set toward the ratchet wheel 112a,it has been found unnecessary to taper the right-hand end of the drum;however, under different circumstances, it may be found desirable toalso taper this drum end.

While the present device has been disclosed for use in verticallyelevating and lowering a load, it will readily be apparent that it isnot limited to such use but can also be used for pulling a load in aplane other than vertical.

In view of the foregoing, it will be apparent to those skilled in theart that we have accomplished at least the principal object of ourinvent-ion and it will also be apparent to those skilled in the art thatthe embodiments herein described may be variously changed and modified,without departing from the spirit of the invention, and that theinvention is capable of uses and has advantages not herein specificallydescribed; hence it will be appreciated that the herein disclosedembodiments are illustrative only, and that our invention is not limitedthereto.

We claim:

1. A hoisting device and the like comprising a frame, a ratchet wheelpivotally supported by said frame, a first pawl supported by said framefor engagement with said ratchet wheel to prevent rotation thereof inone direction and such pawl being pivotable away from engagement withsaid ratchet wheel to provide for rotation thereof in said onedirection, a second pawl swingable in an arcuate path of travel aboutthe axis of rotation of said ratchet wheel and pivotable toward and awayfrom engagement therewith, resilient means yieldably biasing said secondpawl away from ratchet wheel engagement, a first abutment for pivotingsaid second pawl to engagement with said ratchet wheel against the forceexerted by said resilient aneans when said second pawl is swung in itsarcuate path in one direction to abutment engagement, a second abutmentengageable with said first pawl for pivoting the latter away fromengagement with said ratchet wheel upon further movement of said secondpawl in the direction aforesaid, and a resilient lost-motion connectioninterposed between said labutments to delay return of said first pawl toengagement with said ratchet wheel following its disengagement therefromand subsequent reverse movement of said second pawl in its arcuate pathof travel.

2. The construction of claim 1 wherein said second abutment comprises aspring-loaded plunger providing a resilient lost-motion structure whichdelays return of said first pawl to engagement with said ratchet wheelfollowing its disengagement therefrom and subsequent reverse movement ofsaid second pawl in its arcuate path of travel.

3. The construction of claim 2 wherein a helical spring is engaged withsaid plunger to yieldably bias the latter to a predetermined positionfor engagement with said first pawl.

4. The construction of claim 1 wherein said first pawl has a projectionextending radially of such pawls pivotal axis for manual pawl movementaway from ratchet wheel engagement to provide for rapid non-ratchetingrotation of said ratchet wheel.

5. The construction of claim 4 wherein said first pawl projection is onthe opposite side of the pawlaxis from that pawl portion which engagessaid ratchet wheel.

6. A hoisting device and the like comprising a frame, a ratchet wheelpivotally supported by said frame, a first pawl supported by said framefor engagement with said ratchet wheel to prevent rotation thereof inone direction and such pawl being pivotable away from engagement withsaid ratchet wheel to provide for rotation thereof in said onedirection, a second pawl swings-ole in an arcuate path of travel aboutthe axis of rotation of said ratchet wheel and pivotable toward and awayfrom engagement therewith, resilient means yieldably biasing said secondpawl away from ratchet wheel engagement, and an actuating memberadjacent said ratchet wheel and pivotable about the rotational axisthereof, said member having a first abutment for pivoting said secondpawl to engagement with said ratchet wheel against the force exerted bysaid resilient means when said second pawl is swung in its arcuate pathin one direction to engagement with said first abutment and said memberhaving a second abutment for pivoting said first pawl away from engagement with said ratchet wheel upon further movement of said second pawlin the direction aforesaid and consequent rotation of said actuatingmember with said second pawl.

7. The construction of claim 6 wherein said first abutment is shiftablerelative to said actuating member to vary the place of engagement ofsaid second pawl therewith along the latters path of travel. 8. Theconstruction of claim 6 wherein said second abutment comprises anaxially movable plunger biased to a predetermined position forengagement with said first pawl by means of a helical spring, saidplunger and said spring providing a resilient lost-motion structurewhich delays return of said first pawl to engagement with said ratchetwheel following its disengagement therefrom and subsequent reversemovement of said second pawl in its arcuate path of travel.

9. A hoisting device and the like comprising a frame, a ratchet wheelpivotally supported by said frame, a first pawl supported by said framefor engagement with said ratchet wheel to prevent rotation thereof inone direction and such pawl being pivotable away from engagement withsaid ratchet wheel to provide for rotation thereof in said onedirection, an arm pivotable about the rotational aXis of said ratchetwheel, a second pawl pivotally carried by said arm for movement towardand away from ratchet wheel engagement and providing facing abutmentsoff-set to one side of its pivotal axis, said second pawl being bodilyshiftable with said arm for movement in an arcuate path of travel aboutsaid ratchet Wheel axis, a selector member pivotally carried by said armintermediate said second pawl abutments, a plunger slidably carried bysaid selector member for movement transversely of the latters pivotalaxis, and a helical spring yieldably biasing said plunger to engagementwith one or the other of said second pawl abutments, depending upon theposition to which said selector member is pivoted, to yieldably biassaid second pawl toward or away from ratchet wheel engagement.

10. The construction of claim 9 wherein said second pawl has an arcuatesurface, opposed portions of which provide said facing abutments.

11. A hoisting device and the like comprising a frame having spacedportions in side-by-side relation, a ratchet wheel pivotally supportedby and disposed intermediate said spaced frame portions, a dnum inside-by-side relation with said ratchet wheel and rotatable therewith, acable wound upon said drum and adapted to be attached to a weight to belifted, a first pawl pivotally supported between said frame portions forengagement with said ratchet wheel to prevent rotation thereof in adirection to unwind said cable from said drum and such pawl beingmovable about its pivot away from engagement with ratchet wheel toprovide for rotation thereof in the direction aforesaid, a torsionspring disposed about the axis of said pawl and having a finst partengaged with the latter and a second part engaged with an adjoiningframe portion to yieldably bias said pawl ratchet wheel engagement, anactuating arm having spaced portions in side-by-side relation forreceiving said frame therebetween and said arm being pivotable about therotational axis of said ratchet wheel, a second pawl pivotally supportedbetween said arm portions for movement toward and away from ratchetwheel engagement and p'noviding facing abutments off-set to one side ofits pivotal axis, said second pawl being bodily shiftable with said armfor movement in an arcuate path of travel about said ratchet wheel axis,a selector member pivotally carried by one of said arm portionsintermediate said second pawl abutments, a plunger slidably carried bysaid selector member for movement transversely of the latters pivotalaxis, a helical spring yieldably biasing said plunger to engagement withone or the other of said second pawl abutments, depending upon theposition to which said selector member is pivoted, to yieldably biassaid second pawl away from or toward ratchet wheel engagement torespectively provide for ratchet wheel rotation in a direction to unwindsaid cable from said drum or rotation in the oppostie direction, anactuating member intermediate said ratchet wheel and the adjoining frameportion and piv-otable about the rotational axis of said ratchet wheel,a first abutment carried by said actuating member for pivoting saidsecond pawl to engagement with said ratchet wheel against the urging ofsaid selector member plunger when said second pawl is swung in itsarcuate path in one direction to engagement with the first actuatingmember abutment, and a second abutment carried by said actuating memberand engageable with said first pawl for pivoting the latter away fromratchet wheel engagement upon further movement of said second pawl inthe direction aforesaid and consequent rotation of said actuating memberwith said arm.

12. The construction of claim 11 wherein said second actuating memberabutment is provided by an axially movable plunger and wherein a helicalspring is engaged with said plunger to yieldably bias the latter to apredetermined position with respect to said actuating member forengagement with said first pawl, said plunger providing a resilientlost-motion structure which delays return of said first pawl toengagement with said ratchet wheel following its disengagement therefromand subsequent reverse movement of said arm, said second pawl, and saidactuating member.

13. The construction of claim 12 wherein said first actuating memberabutment is shiftable relative to said actuating member to vary theplace of engagement of said second pawl therewith along the latters pathof travel.

14. A hoisting device'and the like comprising a frame, a ratchet Wheelpivotally supported by said frame, a first pawl supported by said framefor engagement with said ratchet wheel to prevent rotation thereof inone direction and such pawl being pivotable away from engagement withsaid ratchet wheel to provide for rotation thereof in said onedirection, a second pawl swingable in an arcuate path of travel aboutthe axis of rotation of said ratchet wheel and pivotable toward and awayfrom engagement therewith, and resilient means formed of a spring-loadedplunger spaced radially of the pivotal axis of said second pawl andacting along a line transverse to such pawl axis to yieldably bias saidsecond pawl selectively toward and away from ratchet wheel engagement.

References Cited in the file of this patent UNITED STATES PATENTS2,581,716 Sasgen Jan. 8, 1952 2,620,996 Le Bus Dec. 9, 1952 2,633,328Wallace Mar. 31, 1953 2,738,954 Du Bois Mar. 20, 1956 2,854,852 ClarkOct. 7, 1958 2,884,226 Palka Apr. 28, 1959 2,890,857 Hoffman June 16,1959 2,913,224 Uhlig Nov. 17, 1959 2,927,771 Clark Mar. 8, 19602,967,046 Ratcliff Ian. 3, 1 961

1. A HOISTING DEVICE AND THE LIKE COMPRISING A FRAME, A RATCHET WHEELPIVOTALLY SUPPORTED BY SAID FRAME, A FIRST PAWL SUPPORTED BY SAID FRAMEFOR ENGAGEMENT WITH SAID RATCHET WHEEL TO PREVENT ROTATION THEREOF INONE DIRECTION AND SUCH PAWL BEING PIVOTABLE AWAY FROM ENGAGEMENT WITHSAID RATCHET WHEEL TO PROVIDE FOR ROTATION THEREOF IN SAID ONEDIRECTION, A SECOND PAWL SWINGABLE IN AN ARCUATE PATH OF TRAVEL ABOUTTHE AXIS OF ROTATION OF SAID RATCHET WHEEL AND PIVOTABLE TOWARD AND AWAYFROM ENGAGEMENT THEREWITH, RESILIENT MEANS YIELDABLY BIASING SAID SECONDPAWL AWAY FROM RATCHET WHEEL ENGAGEMENT, A FIRST ABUTMENT FOR PIVOTINGSAID SECOND PAWL TO ENGAGEMENT WITH SAID RATCHET WHEEL AGAINST THE FORCEEXERTED BY SAID RESILIENT MEANS WHEN SAID SECOND PAWL IS SWUNG IN ITSARCUATE PATH IN ONE DIRECTION TO ABUTMENT ENGAGEMENT, A SECOND ABUTMENTENGAGEABLE WITH SAID FIRST PAWL FOR PIVOTING THE LATTER AWAY FROMENGAGEMENT WITH SAID RATCHET WHEEL UPON FURTHER MOVEMENT OF SAID SECONDPAWL IN THE DIRECTION AFORESAID, AND A RESILIENT LOST-MOTION CONNECTIONINTERPOSED BETWEEN SAID ABUTMENTS TO DELAY RETURN OF SAID FIRST PAWL TOENGAGEMENT WITH SAID RATCHET WHEEL FOLLOWING ITS DISENGAGEMENT THEREFROMAND SUBSEQUENT REVERSE MOVEMENT OF SAID SECOND PAWL IN ITS ARCUATE PATHOF TRAVEL.